Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Traffic matrix estimation on a large IP backbone: a comparison on real data
KTH, Superseded Departments, Signals, Sensors and Systems.
2004 (English)In: IMC '04 Proceedings of the 4th ACM SIGCOMM conference on Internet measurement, 2004, 149-160 p.Conference paper, Published paper (Refereed)
Abstract [en]

This paper considers the problem of estimating the point-to-point traffic matrix in an operational IP backbone. Contrary to previous studies, that have used a partial traffic matrix or demands estimated from aggregated Netflow traces, we use a unique data set of complete traffic matrices from a global IP network measured over five-minute intervals. This allows us to do an accurate data analysis on the time-scale of typical link-load measurements and enables us to make a balanced evaluation of different traffic matrix estimation techniques. We describe the data collection infrastructure, present spatial and temporal demand distributions, investigate the stability of fan-out factors, and analyze the mean-variance relationships between demands. We perform a critical evaluation of existing and novel methods for traffic matrix estimation, including recursive fanout estimation, worst-case bounds, regularized estimation techniques, and methods that rely on mean variance relationships. We discuss the weaknesses and strengths of the various methods, and highlight differences in the results for the European and American subnetworks.

Place, publisher, year, edition, pages
2004. 149-160 p.
Keyword [en]
Traffic matrix estimation, Optimization, SNMP, MPLS
National Category
Telecommunications
Identifiers
URN: urn:nbn:se:kth:diva-7729DOI: 10.1145/1028788.1028807Scopus ID: 2-s2.0-14944378851OAI: oai:DiVA.org:kth-7729DiVA: diva2:12841
Conference
IMC’04 October 25–27, 2004, Taormina, Sicily, Italy
Note
QC 20101105Available from: 2007-11-25 Created: 2007-11-25 Last updated: 2012-03-02Bibliographically approved
In thesis
1. Towards robust traffic engineering in IP networks
Open this publication in new window or tab >>Towards robust traffic engineering in IP networks
2007 (English)Licentiate thesis, comprehensive summary (Other scientific)
Abstract [en]

To deliver a reliable communication service it is essential for the network operator to manage how traffic flows in the network. The paths taken by the traffic is controlled by the routing function. Traditional ways of tuning routing in IP networks are designed to be simple to manage and are not designed to adapt to the traffic situation in the network. This can lead to congestion in parts of the network while other parts of the network are far from fully utilized. In this thesis we explore issues related to optimization of the routing function to balance load in the network.

We investigate methods for efficient derivation of the traffic situation using link count measurements. The advantage of using link counts is that they are easily obtained and yield a very limited amount of data. We evaluate and show that estimation based on link counts give the operator a fast and accurate description of the traffic demands. For the evaluation we have access to a unique data set of complete traffic demands from an operational IP backbone.

Furthermore, we evaluate performance of search heuristics to set weights in link-state routing protocols. For the evaluation we have access to complete traffic data from a Tier-1 IP network. Our findings confirm previous studies that use partial traffic data or synthetic traffic data. We find that optimization using estimated traffic demands has little significance to the performance of the load balancing.

Finally, we device an algorithm that finds a routing setting that is robust to shifts in traffic patterns due to changes in the interdomain routing. A set of worst case scenarios caused by the interdomain routing changes is identified and used to solve a robust routing problem. The evaluation indicates that performance of the robust routing is close to optimal for a wide variety of traffic scenarios.

The main contribution of this thesis is that we demonstrate that it is possible to estimate the traffic matrix with good accuracy and to develop methods that optimize the routing settings to give strong and robust network performance. Only minor changes might be necessary in order to implement our algorithms in existing networks.

Place, publisher, year, edition, pages
Stockholm: KTH, 2007. xi, 36 p.
Series
Trita-EE, ISSN 1653-5146 ; 2007:073
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-4557 (URN)978-91-7178-816-0 (ISBN)
Presentation
2007-12-10, Q31, KTH, Osquldas väg 6, Stockholm, 10:00
Opponent
Supervisors
Note
QC 20101105Available from: 2007-11-25 Created: 2007-11-25 Last updated: 2010-11-05Bibliographically approved
2. Aspects of proactive traffic engineering in IP networks
Open this publication in new window or tab >>Aspects of proactive traffic engineering in IP networks
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

To deliver a reliable communication service over the Internet it is essential for the network operator to manage the traffic situation in the network. The traffic situation is controlled by the routing function which determines what path traffic follows from source to destination.  Current practices for setting routing parameters in IP networks are designed to be simple to manage. This can lead to congestion in parts of the network while other parts of the network are far from fully utilized. In this thesis we explore issues related to optimization of the routing function to balance load in the network and efficiently deliver a reliable communication service to the users. The optimization takes into account not only the traffic situation under normal operational conditions, but also traffic situations that appear under a wide variety of circumstances deviating from the nominal case. In order to balance load in the network knowledge of the traffic situations is needed. Consequently, in this thesis we investigate methods for efficient derivation of the traffic situation. The derivation is based on estimation of traffic demands from link load measurements. The advantage of using link load measurements is that they are easily obtained and consist  of a limited amount of data that need to be processed. We evaluate and demonstrate how estimation based on link counts gives the operator a fast and accurate description of the traffic demands. For the evaluation we have access to a unique data set of complete traffic demands from an operational IP backbone.  However, to honor service level agreements at all times the variability of the traffic needs to be accounted for in the load balancing. In addition, optimization techniques are often sensitive to errors and variations in input data. Hence, when an optimized routing setting is subjected to real traffic demands in the network, performance often deviate from what can be anticipated from the optimization. Thus, we identify and model different traffic uncertainties and describe how the routing setting can be optimized, not only for a nominal case, but for a wide range of different traffic situations that might appear in the network.  Our results can be applied in MPLS enabled networks as well as in networks using link state routing protocols such as the widely used OSPF and IS-IS protocols. Only minor changes may be needed in current networks to implement our algorithms. The contributions of this thesis is that we: demonstrate that it is possible to estimate the traffic matrix with acceptable precision, and we develop methods and models for common traffic uncertainties to account for these uncertainties in the optimization of the routing configuration. In addition, we identify important properties in the structure of the traffic to successfully balance uncertain and varying traffic demands.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2011. xi, 63 p.
Series
Trita-EE, ISSN 1653-5146
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-29558 (URN)978-91-7415-870-0 (ISBN)
Public defence
2011-03-01, F3, Lindstedtsvägen 26, KTH, Stockholm, 13:00 (English)
Supervisors
Note
QC 20110211Available from: 2011-02-11 Created: 2011-02-07 Last updated: 2011-02-11Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Gunnar, AndersJohansson, Mikael
By organisation
Signals, Sensors and Systems
Telecommunications

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 266 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf